I replaced my reverse and low gears in the sub-transmission this week. It was my first time going through the sub-trans, but I learned a lot that is useful to pass on to anyone getting into this.
The first part of this is a guide to removing the sub-trans. You may need to get into it for various reasons, whether replacing your reverse gears, upgrading to Talon reverse gears, replacing your low gear, etc. Whatever you're doing, you'll need new gaskets ready for replacement:
21206-HL4-003 | GASKET, SUB-TRANSMISSION CASE |
21205-HL4-003 | GASKET, SUB-TRANSMISSION COVER |
The manual also wants you to have on hand some liquid sealant for re-assembly. They specify TB1207B by Threebond or equivalent. (Manual page 12-7, PDF 377)
Also, have a look at your output seals before you order parts. I had oil around my rear output seal, so I ordered and replaced that one. It's not a bad idea to just go ahead and replace both while you're in there, if you choose.
We'll follow the service manual, but I will attempt to fill in some gaps in the manual, and to let you know what steps are necessary and some that can be skipped.
One of the difficulties of working with the service manual is putting together the order of operations, as it has you jump all around the pages. The first thing I did was to break out all of the steps in order, and I'll list the corresponding manual page (and it's PDF page number, in case you're viewing the manual electronically.)
We'll start with the steps to remove the sub-trans. Later, I'll share what I can regarding the internals and reverse gear replacement.
Step | Description | PDF page | Manual page | Comments |
1 | Remove front seat cushion | 82 | 2-4 | |
2 | Remove rear side cover (gas tank panel) | 87 | 2-9 | skipped |
3 | Remove front seat back | 83 | 2-5 | |
4 | Remove rear center cover (between seat cushion and seat back) | 86 | 2-8 | |
5 | Remove heat shielding (comfort kit) | | | |
6 | Remove front doors | 96 | 2-18 | skipped |
7 | Remove front side covers (flares) | 91 | 2-13 | skipped |
8 | Remove floor panel | 92 | 2-14 | skipped |
9 | Remove Air Cleaner Cover | 104 | 2-26 | skipped |
10 | Remove Snorkel Duct A | 239 | 7-17 | loosened frame mount only |
11 | Remove front bumper | 93 | 2-15 | May be optional? |
12 | Remove skid plate | 109 | 2-31 | |
13 | Sub Trans | 375 | 12-5 | |
14 | Drain oil | 150 | 3-16 | |
15 | Disconnect vent line | 375 | 12-5 | |
16 | Remove pinch bolt and shift arm | 375 | 12-5 | |
17 | Remove bolts and stay | 375 | 12-5 | |
18 | Front Differential | 375 | 12-5 | |
19 | Disconnect lock switch | 375 | 12-5 | skipped |
20 | Disconnect front VS sensor | 375 | 12-5 | skipped |
21 | Support front gear case | 375 | 12-5 | |
22 | Remove brackets and bolts | 375 | 12-5 | |
23 | Move front diff forward fully | 376 | 12-6 | |
24 | Disconnect front drive shaft from sub trans | 376 | 12-6 | |
25 | Remove spring and o-ring | 376 | 12-6 | |
26 | On the front of the Sub-Trans | 376 | 12-6 | |
27 | Disconnect vs sensor plug | 376 | 12-6 | |
28 | Release wire clip | 376 | 12-6 | |
29 | release water pump breather hose | 376 | 12-6 | |
30 | Remove bolts, sub-trans position switch, and o-ring | 376 | 12-6 | |
31 | Down below - Remove 3 bolts | 376 | 12-6 | |
32 | Remove 2 bolts | 377 | 12-7 | |
33 | Remove 2 acorn nuts and washers | 377 | 12-7 | |
34 | REMOVE SUB-TRANS ASSEMBLY | 377 | 12-7 | |
35 | Remove dowel pins, gasket, and damper | 377 | 12-7 | |